Random Sampling and Making Inferences

A recent survey of 800 seventh graders from across the state shows 4 out of 10 like to play paper football. How many students said they like to play paper football?

• 40 students

• 200 students 

• 320 students

• 8,000 students

Assign each car in a dealership a number and then use a random-number table to select the cars to be inspected. 

• systematic

• random sample

• convenience

• biased sampling

Zoie completes a report by asking 70 students across campus. She found that 48% of CIAA students do not wash their hands after using the bathroom. What is the population of her survey?

• the bathroom

• CIAA students

• 48% of students

What inference can you draw from this survey?

• I can infer that most students in this school like pizza.

• I can infer that very few students like hamburgers.

• I can infer that their favorite is corn dogs.

• I can infer that most students in this school like hamburgers.

The dot plot shows a random sample of the number of fish caught and released by 30 participants during a two-day fishing tournament. Select the inference that can be made based on the data collected.

• On average, most participants caught and released 5 or more fish.

• More participants caught 6 fish than any other number.

• The same participants who caught and released 1 fish the first day caught and released 1 fish on the second day.

• On average, participants caught and released more fish on Day 2.

A travel club has 3,000 members. A random sample of 50 of the club members found that 12 people like mountain vacations best. Which statement is NOT supported by the sample data?

• Twenty-four percent of those sampled say they like mountain vacations best.

• An estimated 720 club members would likely say they enjoy mountain vacations best.

• Almost one-quarter of club members would likely say they enjoy mountain vacations best.

• More than 2,500 club members would likely say they prefer other vacations over mountain vacations.

The dot plots show the number of calls that two radio stations receive each day for a ten-day period. The two shows are shown at the same time. Which of the following inferences based on the median values is valid?

• The radio shows receive similar amounts of calls.

• Radio Show 1 generally receives more calls.

• Radio Show 2 generally receives more calls.

Margo wants to convince her father to change her curfew from 9 P.M. to 10 P.M. She gathers data on curfew times from a random sample of students at her middle school. Can Margo use these data to present a valid inference that will convince her father? Explain.

• Yes; Most students have a curfew of 10 P.M. or later.

• Yes; More students have a curfew of 9 P.M. than any other time.

• No; Most students have a curfew of 9 P.M. or earlier.

• No; More students have a curfew of 10 P.M. or 11 P.M. than 8 P.M.

Ana wants to know the average student’s opinion of the tardy policy at her school. Which group of students should she survey in order to achieve the most accurate results?

• Thirty randomly selected students from her school

• Thirty students who are rarely tardy

• thirty of her friends

There are 400 students at Polly's school. She surveyed a random sample of 80 students to find their favorite hobby. 19 said they like to read. 30 said they like to be with friends. 8 said they like to do crafts. 23 said they like to play sports. Polly infers that doing crafts is the least popular hobby at her school. Refer to the data table. Polly surveys two more samples. Do the results from these samples support the inference made from the first sample?

• Yes, the survey results support the inference that doing crafts is the least popular hobby at Polly's school.

• No, the survey results does not support the inference that doing crafts is the least popular hobby at Polly's school.